Gaseous electric discharge device



June 11 1935. c, 80L ET AL 2,004,565

GASEOUS ELECTRIC DISCHARGE DEVICE Filed June 18, 1934 MGR-32W Patented June 'UNITED STATES, PATENT or power is wasted.

The object of the a starting and In accordance with thi ovel starting and If a. choke purpose the apparatus has and if an ohmic resistance Cornelis Bo Netherlands, Company, a corpo Application June 18, 1934, Serial FICE I 2,004,565 GASEOUS ELECTRIC DISCHARGE DEVICE l and Eduard G.

assignors to Dorgelo, Eindhoven, General Electric ration of New York In the Netherlands June 24, 1933 3 Claims.

onnected in series -coil is used for this a low power factor, is used a quantity of the current this can be group of discharge devices and connecting the mid-point of the choke coil to the' third terminal of the current source through an impedance.

When the gaseous mprisesthe vapor of a difiicultly vaporizable vices as above of the invention,

Fig. 2 is a similar view of another embodiment of the invention, and

Fig. 3 is a similar view of still ment of the invention.

Like numbers denote like parts in all the figures.

The embodiment of the inventi n illustrated another embodimixture of argon and or neon and sodium vapor.

A chokecoil 2 is connected in series with each pair of I and between the members, of each pair of said devices I is connected 4 of the secondary 1 of said devices pair. Each across the leads 3 and 5 a three-phase transiormer.- The mid-point of the choke-coil 2 is connected through a condenser 5 to the conductor 6 of said secondary 1. A Switch 8 is connected into said conductor 6. x The apparatus is started into operation by closing switch 8 which connects said discharge devices I in series with one half of the choke coil 2 and the condenser 5 across two separate phases of the three phase current source. After the dis- -charge devices I have been started into operation the switch 8 is moved to its contact breaking position and each pair of discharge devices I together with the choke coil 2 for the pair is then connected in series across the third phase of the current sources said discharge devices I during the'starting period I is thus considerably higher than the voltage applied thereto during the operation thereof. The discharge devices I are thus started into operation and the choke coil 2 is of smaller dimensions than it could be if it had to absorb the difierence between the starting voltage and the operating voltage during the operation of the discharge devices I. The choke-coil 2 is made of suflicient size to merely perform the function of stabilizing the discharge in said devices I. This improves the power factor of the apparatus and a higher operating voltage can be used for the discharge devices I.

When the gaseous atmosphere of devices I comprises the vapor of, a difiicultly vaporizable material, such as sodium, the condenser 5 is of such size that the impedance thereoi is considerably greaterthan twice that of one-half the choke-coil 2. Rapid heating of the container of the discharge devices I is thus effected and the discharge the vaporizable material is quickly vaporized to rapidly build up an efiective in said device.

It is obvious that the number of groups of discharge devices I can be increased. As the midpoint of each of said choke-coils 2 is connected to a conductor 8 common to all of the mid-points a single switch 8 connected into the common conductor 8 is sufficient. When desired, the switch 8 is left in its contact making position an appreciable time after the discharge devices I have been started into operation to overload said devices I which causes rapid heating of the devices I to quickly vaporize the vaporizable material therein and rapidly build up an effective metal vapor pressure. The switch 8 can be provided with a timing means, such as a thermostatic element controlled by the temperature of said devices, to delay the opening thereof until said discharge devices I have reached their operating temperature. It is likewise obvious that more than one tube can be connected on each side of the midpoint of each group. i

The embodiment of the invention illustrated in Fig. 2 of the drawing is similar to that illustrated in Fig. 1 except that in this embodiment two discharge devices I are connected in parallel on either side of the mid-point of the group. Each discharge device in this circuit has a choke-coil 9 connected in series therewith and the midpoint of the group is connected directly, without metal vapor pressure j illustrated in Fig. 2 of the drawing illumination of roads, airports or the like the The voltage applied to each ofa condenser, to the third terminal of the alternating current source.

The discharge devices I in each group are separated a considerable distance, when desired. For example, when the embodiment of the invention is used for the leads 3 and 4 extend from either side of the secondary 1 as shown in Fig. 3 of the drawing.

While we have shown and described and have pointed out in the annexed claims certain novel features of the invention, it will be understood that various omissions, substitutions and changes in the forms and details of the device illustrated and in its use'and operation may be made by those skilledin the art without departing from the broad spirit and scope of the invention, for example, when switch 8 is in its open circuit position it can be connected to the star point of the alternating current source, when desired.

What we claim as new and desire to secure by Letters Patent of the United States is:-

1. A starting and operating circuit for a plu-' rality of gaseous electric discharge devices comprising in combination, a three-phase alternating current source for said devices, a series connected stabilizing impedance for said devices, said devices being connected in groups comprising at least two of said devices, the devices in each group being connected in series across two terminals of said current source and means to connect the mid-point of each group said current source during the starting period of said devices and to disconnect the mid-point from the thifd terminal during the operation of said devices.

2. A starting and operating circuit for a plurality of gaseous electric discharge devices com prising in combination, a three-phase alternating current source for said devices, said devices being comprising at least two of said devices, the devices ineach group being connected in series across two terminals of said current source, an impedance connected in series with and between the devicesin each group, means to connect the mid-point of said impedance to the third terminal of said current source during the starting period of said device and to:

least two of said devices, the devices in each group being connected in series across two terminals of- -"n one of said being connected in parallel with the devices in another of said groups, the mid-point of each group being connected to a common conductor and means to connect said common conductor to the third terminal of said current source during the starting of said devices and to disconnect said conductor from said terminal during the operation of said devices. CORNELIS BOL. EDUARD G. DORGELO,

groups for said devices, a series connected to the third terminal of 

